Hemminki 2004.

Methods	Randomised controlled trial
Data	Setting: 'local clinics', Estonia. 4295 postmenopausal women aged 50 to 64
Comparisons	Investigated the effect of different design methods Non‐blinded allocation comparing active HRT treatment versus no treatment. This was compared to traditional blinded allocation comparing active HRT treatment versus placebo.
Outcomes	Proportion recruited to trial
Notes
Risk of bias
Item	Authors' judgement	Description
Random Sequence generation ok?	Yes	Computer‐based random number sequence
Allocation concealment?	Yes	Sealed opaque envelope with ID on it
Blinding of participants and personnel ok?	Yes	Blinding only partial but looking at the effect of open study design was the purpose of the study
Blinding of outcome assessment ok?	Yes	Partial (see above) but objective outcome
Incomplete outcome data handled ok?	Yes	Adequate
Free of selective reporting?	Yes	Recruitment outcome presented, which is all the review needs
Was the study free of other bias?	Yes	No other biases apparent
Overall bias?	No	Low risk of bias